Re: [PSUBS-MAILIST] Hatch design

["Captain Nemo" <vulcania@interpac.net>]

(SNIP)

> I thought of that.  In fact saw the idea on George's Video I think.. I was
> trying to come up with an easier way, although that is reasonably easy..
I
> am making a small double axle trailer, so If everything is ballanced
> properly, I might be able to get away without a front wheel..HHHMMMM...
>
> dale.


Dale,

I haven't seen the video, but I've heard George did it with a trike trailer
and cable.  So we know the method is reliable.

A tongue might or might not be easier; depends.  How long would it have to
be?  I launched on a moderately steep Marina boatramp.  There, the sub was
maybe 30 feet out from the water's edge when she reached the four-foot depth
at which she floated free of the trailer.  And then, the van I used was
about 15 feet up from the waterline (lost about 5-feet of cable making loops
in the ends, securing, and such).  A 45-foot tongue is going to be one hefty
piece of steel, isn't it?  Might need to be quite a feat of engineering.

All I did was take a homemade boat trailer; build in a keel-mount over the
axle, and a tail-mount up toward  the tongue.  With the sub sitting
nose-high and backwards when towed on level ground, she met the water
head-on and level on the inclined ramp, which made launch and recovery
really easy.  (The wooden ramps that once supported a Chris Craft were
retained as "catwalks" for boarding, exit, and support crew use.)

For the trike gear, all I did was gusset-and-weld a short section of 3" OD
pipe perpendicular on the trailer tongue; welded a shorter section of 3" ID
pipe to the hub-hole of a spare tire; greased 'em and slipped one over the
other, and held the wheel on the axle with a 1" wide ring of 3" ID pipe that
served as an outer locking collar with a throughbolt retainer.  It was
slip-fit and covered-wagon tech, to be sure; but when traveling less than
100 feet at speeds under 1/10th MPH, it worked well.

In use, my crew (Lynn) and I would throw the third wheel into the van;
trailer the sub to the Marina; back onto the ramp; chock the trailer tires;
disengage the hitch and lift the trailer tongue with a floor jack; install
the third wheel with the locking collar; and set her down on the ground.
Then I'd hook the cable to the trailer, pull the van forward, and hook the
cable to the van.  Ready to launch, I'd pull the trailer slightly forward,
Lynn would pull the chocks, and  gravity would roll the trailer into the
water while I controlled the launch from the van.

For recovery, I'd motor the sub in reverse over the trailer; Lynn would
attach a securing strap to the tailfin, and we'd pull her out (still on the
cable) with the van.  Once out of the water, I'd disconnect the cable,
remove the wheel, hook up and tow her home.  All-in-all, it probably added
maybe 10 minutes to the launch time, and as much again to recovery.  That
really wasn't a problem, because we had pre-and-post float checks and tasks
to perform; and it gave us time to talk to the spectators who showed  up to
see what we were doing (the police, fire-department, Marina manager, etc.)

I suppose a special trailer with a built-in extendable tongue would be
faster and easier; but again: how long is it going to have to be, and what
kind of engineering is it going to require?  All things considered, a
trike-trailer and cable are cheap, easy, and work really well on a wide
variety of ramps.  And if you included a winch, you could make the
cable-layout part of the  process even easier.

Anyway, whatever you decide to use, I'm confident you'll be able to make it
work, and we all wish you the best of luck with your soon-to-be-wet
submarine.

But tell us: does it still seem like a dream?  Can you believe you're really
about to actually do it?  How do you feel, now that the first test is
getting close?

I got maybe 40 minutes of sleep the night before we dunked the Nautilus for
the first time; I was scared spitless (that it might not float, more than
anything else) and when that 04:30 launch-prep hour arrived, every cell in
my body wanted to roll over and go back to sleep.  But after coming that
far, it was out of my hands.  I had to do it.  And after years of research,
development, and construction, that first float was an indescribably special
moment in my life.

I've surfed big waves, jumped out of airplanes, flown through thunderstorms,
hunted pterodactyls, and choked wolves to death bare handed (OK, maybe I
didn't do those last two things); but NOTHING exceeds the feeling you get
when you build your own submarine, dive it, and surface for the first time.
It's a once-in-a-lifetime experience; a unique individual accomplishment;
and it's right around the corner for you.

Congratulations, and good luck on your first dive.

Pat